Lighting fixture and method of installing same



June 27, 1967 A. F. JACOBS 3,328,576

LIGHTING FIXTURE AND METHOD OF INSTALLING SAME Filed Jan. 14, 1965 I NVE NTOR.

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United States Patent 3,328,576 LIGHTING FIXTURE AND METHOD OF INSTALLHNGSAMTE Arthur F. Jacobs, Los Angeles, Calif., assignor to PrudentialLighting Corporation, Los Angeles, Caiifi, a

corporation of California Filed Jan. 14, 1965, Ser. No. 425,400 12Claims. (Cl. 2405i.11)

The present invention relates to a lighting fixture and a method ofinstalling the same, and more particularly to a unitary fluorescentlighting fixture adapted for rapid and simplified installation on asuspended grid-type ceiling without the use of tools.

Suspended ceilings comprised of panels laid on a grid assembly of T-barsoffer many advantages, such as attractive appearance, simplicity ofconstruction and the provision of an easily accessible space above theceilings for running conduits, power lines and the like. Ceilings ofthis .type are frequently, employed in new building construction, aswell as in the modernization of old buildings by lowering the ceilingline.

Fluorescent lighting fixtures are invariably used with this type ofceiling and various types of connecting means have been employedheretofore for installing such fixtures on the ceiling; for example,hooks or hangers connected to the T-bars with the fluorescent tubessuspended therebelow. The installation of lighting fixtures with priorart connecting means, however, has been 1aborious and time consuming.The ceiling connections are often located in an awkward place forworking, particularly when installation requires the use of tools.Further, the location of the mounting means, as well as wireways, belowthe ceiling line detracts from the appearance of the ceiling.

The present invention provides a unitary lighting fixture which can beeasily and quickly installed on a gridtype ceiling. In a matter ofseconds, one end of the lighting fixture is fastened and then the otherend is pivoted into a fastened relationship without the use of anytools. Upon installation, the mounting means is completely concealedfrom view and only the fluorescent tubes and lamp support means areexposed below the ceiling. If desired, a light diffuser may be snappedon to the lamp support means. The exposed portion of the fixture is thuscontained in a compact and relatively flat attractive structuresuspended only a minimum distance from the ceiling.

A general object of the present invention is to provide a lightingfixture which overcomes the aforementioned disadvantages of prior artstructures.

Another object is to provide a lighting fixture adapted for fast andsimplified installation on a grid-type ceiling without the requirementof tools.

A further object is to provide a fluorescent lighting fixture which isinstalled to a grid-type ceiling with the mounting means concealed fromview.

Still another object is to provide a practical, simplified andeconomical method of installing an elongated lighting fixture on agrid-type ceiling.

Other objects and advantages will be readily apparent from a reading ofthe following detailed description and accompanying drawing wherein:

FIG. 1 is an isometric view of an exemplary lighting fixture installedon a grid-type suspended ceiling;

FIG. 2 is a vertical side View of the lighting fixture installed on theceiling with portions cut away and portions shown in cross-section tofacilitate understanding;

FIG. 3 is a vertical end view of the lighting fixture taken along planeIII--III of FIG. 2; and

FIG. 4 is a top .plan view of the lighting fixture and the ceilingshowing the method of installation.

Referring now to the drawing wherein like reference numerals designatelike or corresponding parts throughout the several views, there is shownin FIG. 1 an exemplary lighting fixture 10 which is installed on asuspended ceiling. The suspended ceiling may include a grid arrange-mentof T-shaped bars 12 which are spaced and disposed perpendicularly withrespect to one another so as to define a plurality of rectangularopenings 14 for receiving panels 16.

The T bars 12 may be disposed in an inverted position with flangeportion 12a (FIG. 3) extending horizontally and flange portion 12bextending vertically therefrom. Flange portions 12a of theperpendicularly disposed T bars provide a ledge about the periphery ofeach opening 14 to support panels 16. The panels may be constructed ofany suitable material such as cork, Masonite, plastic, fiberboard, woodand the like.

The lighting fixture 10' is comprised of a novel arrangement of elementsin novel relationship to provide a structure which can be easily andquickly installed on the ceiling. As shown in FIGS. 2 and 3, fixture 10may be provided with an elongated horizontally extending light mountingmeans, such as mounting bar 18, which may be disposed transverselyacross the top edges of a parallel series of the T bars 12 of thesuspended ceiling so that the longitudinal axis of the mounting bar 18extends substantially normal to the longitudinal axes of the T bars onwhich it rests. The load of the lighting fixture is thereforedistributed equally on all of the T bars located between the ends of themounting bar.

Mounting bar 18 may include an elongated hollow channel 18a openingupwardly and having upwardly extending legs diverging slightly from oneanother and terminating in outwardly turned longitudinal flanges. Anelongated top 18b with inwardly turned longitudinal flanges may slidablyengage channel 18a along the tops of its legs so that the channel can beopened and closed as desired. The enclosed channel will provide an idealspace or wireway for receiving the wires required for connecting thelamps, such as fluorescent lighting tubes 20, to a power source.

A pair of lamp support means 22 may be provided to support fluorescenttubes 20 and contain the sockets therefor. The lamp support means areoppositely disposed horizontally in spaced relationship, each lampsupport means being connected to a respective end of the mounting bar 18by a pivotal connecting means 24 (FIG. 2), described in detailhereinafter. Each lamp support means 22 may include a socket platform22a and lamp sockets 22b secured to each platform in a laterally spacedrelationship with respect to the longitudinal axis of the mounting bar18. The socket platform 22a may contain electrical terminals and wiringfrom the sockets 22b. The number of lamp sockets employed may be variedwith the number of lamps or fluorescent tubes desired on the fixture.

It is desirable that the lighting fixture 10 be adapted for quick andeasy installation on the ceiling. This may be accomplished by providingeach lamp support means 22 with bar fastening means 26, which willreleasably fasten each lamp support means to a respective T bar flange12a. A pair of bar fastening means, exemplified by the flexible Clips 26shown in FIG. 2,'may be secured to the top of the socket platform 22aand may extend outwardly horizontally to overlap and slidabiy engagehorizontal T bar flange 12a so that the flange is snugly receivedbetween the clip and the top of the socket platform. The bar fasteningmeans 25 should be sufficiently flexible to enable the lampsupport means22 to be fastened and unfastened many times and to allow a workman toslide the lamp support means. along the T bar flange 12a when in thefastened condition. However, the bar fastening means should besufficiently rigid to snugly retain the lamp support means in thefastened condition. A number of bar fastening means may be employed,depending upon the requirements. They may be laterally spaced from oneanother with respect to the longitudinal axis of the mounting bar 18. Ifdesired, the bar fastening means may be formed from the socket platformitself, for example, by cutting a portion of the top surfaces of thesocketplatform 22a in the form of a tongue and lifting the cut portionaway from the horizontal plane of the platform.

The pivotal connecting means support means 22 to the mounting bar 18,and permits lighting fixture to be easily and quickly installed on thesuspended ceiling in a manner such that only the lamp support means andfluorescent tubes are visible below the ceiling. As shown in FIG. 2, theconnecting means 24 I may pivotally connect each lamp support means 22located below the mounting bar 18 to opposite end portionsof themounting bar, witheach pivotal axis extending substantiallyperpendicular to the longitudinal axis of the mounting bar and extendingvertically when the mounting bar rests transverse the T-bars.

Pivotal connecting means 24 may also position each lamp support means 22below and adjacent the bottom of the T-bar flanges 12a when the mountingbar 18 is resting transversely on the top edges of the vertical flangeportions 12b. In order to accomplish this the height of connecting means24 is such that when placed in position in the manner describedhereinafter the resultant vertical distance between the top of thesocket platform 22a and the bottom of the mounting bar 18' is at leastas great as the height of the T-bars 12. Accordingly, this arrangementwill expose below the ceiling only that portion of the lighting fixture10 which is located below the top of the socket platform 22a.

As shown in FIG. 3, pivotal connecting means 24 may further position thecenter 220 of the lamp support means in a laterally offset location withrespect to a vertical plane passing through the longitudinal axis of themounting bar 18. This offset distance maybe such that when the lampsupport means 22 is fastened to the T-bar flanges 12a the center 22c ofthe lamp support means will lie directly beneath a cross T-bar whichextends parallel to the mounting bar 18(see FIG. 3). Accordingly, uponinstallation, the lamp support means 22 will lie directly below thisT-bar, resulting in an attractive and symmetrical appearance.

The pivotal connecting means 24 may further position the lamp supportmeans 22 in a predetermined horizontally space relationship at oppositeends of the mounting bar 18 so that each pair of bar fastening means 26is adapted to clip onto a respective and selected T-bar flange 12a. Themounting bar 18 may be cut to a proper length to provide for thisdistance or may be bayoneted or telescoped intermediate its ends so thatits length can be selectively adjusted.

Pivotal connecting means 24 may include a cylinder, such as hollowcylinder 24a, with the top end extending through an opening 27 in thebottom of channel 18:: and the bottom end extending through an opening28 in the top of socket platform 22a. The respective ends of cylinder24a are rotatable within channel 18a and socket platform 22a, and may beflared outwardly to be retained therein.

Collars 2412 may be connected adjacent each end of 24 connects the lampcylinder 240, with the top collar slidably engaging the bottom ofchannel 18a and the bottom collar slidably engaging the top of socketplatform 22a. Collars 24b may be connected to the cylinder by anysuitable means such as by press fitting, knurling or spotweldingpAccordingly, upon fastening one lamp support means-22 to a T barat one end of the mounting bar 18, this type Of connection permits theoppositely disposed lamp support means to be pivoted about the fastenedlamp support means for fastening to a selected T bar at the other end ofthe mounting bar.

The lighting fixture may also be provided with means adapted to restrainit from twisting movement when installed on the ceiling. The restrainingmeans may include end plates 18c which may be connected at each end ofmounting bar 18 to portions 18d of the channel top 18b which areslidingly separable therefrom. Each end plate 18c may have a downwardlydirected lug for engaging the outer side T-bar as shown in FIG. 2. Topportions 18 d may he slid on and off the longitudinal flanges of thechannel legs to engage or disengage the lug with a respective T-bar.

The separable channel top portions 18d may also provide quick access tothe end portions of channel 18a for the purpose of making requiredelectrical connections. A knock-out plug 186 may be provided in the endpiece 18c so that wires may be run from the lighting fixture to anelectrical power source.

Lighting fixture 10 may be further retained in its installed position bya weight 28 which may be constructed of a heavy material, such as lead,and may be grooved to conform substantially to the shape of channel top18b so that it can he slid easily along the top of the mounting bar orremoved therefrom.

Upon installation of the lighting fixture the mounting bar 18 isdisposed on top of the T-bars 12 and lamp sup port means 22 are disposedtherebelow. This may be accomplished by passing the lighting fixture 10upwardly through one of the openings 14 and then bringing the lampsupport means 22 down below the T-bars. As shown in FIG. 4 one end ofthe lighting fixture is fastened to a T-bar flange 12a by a pair of barfastening means 26, with the center 220 of the lamp support meanspositioned directly below a vertical portion 12b of a T-bar (see FIG.3). This will fasten one end of the lighting fixture. Next, the fixtureis positioned with its longitudinal axis transverse a plurality ofparallel T-bars 12 (as shown in the phantom position in FIG. 4) with thebar fastening means 26 on the socket platform 22a at the other end ofthe fixture still disengaged from horizontal portion 12a of its adjacentT-bar.

The unfastened end of the lighting fixture is then pivoted about pivotalconnecting means 24 at the fastened end and bar fastening means .26 ofthe unfastened end is brought into fastening engagement with flange 12aof the T-bar adjacent that end. The bar fastening means 26 may he slidalong the T-bar flange during the pivoting operation until the center ofthe second lamp support means is positioned directly below the T-bar.The lighting fixture is now in its installed position. Thereafterthe'weight 28 may be mounted and wiring connections made. The mountingbar top portions 18d may then be slid into place so that the end plateswill further prevent twisting of the lighting fixture.

After installation of the lighting fixture panels 16 may be easily laidin place. No alteration is required of the panels except for the paneladjacent each end of the lighting fixture which may be pre-slotted toreceive the cylinder 24a, the slot remaining concealed above the socketplatform 22a.

The fluorescent lighting tubes 20 may be mounted during any part of theinstallation, but are preferably mounted after the, ceiling has beencompleted.

The instant invention is not limited to fixtures using fluorescenttubes-but may be adapted for fixtures in which of thevertical portion12b of the a number of ordinary light bulbs are supported at each end.Further, the invention is not limited to fixtures for ceilings whichhave a grid arrangement of T-bars but may be adapted for any ceilingcomprised of spaced apart structural members.

It is apparent that the present invention provides a unitary lightingfixture adapted for rapid and simplified installation on a suspendedceiling whereby the mounting means is not exposed below the ceilingline. The present invention further provides a quick and economic methodof installation which obviates the necessity for tools. The lightingfixture of the present invention is also adapted for simple and economicconstruction and maintenance.

It is to be understood that various modifications and variations may bemade in the present invention without departing from the spirit thereofand the scope of the appended claims.

I claim:

1. A unitary fluorescent lighting fixture adapted for rapid andsimplified installation on a suspended ceiling having a grid arrangementof inverted T-bars and cross T-bars comprising:

(a) an elongated mounting means adapted to rest transversely across thetops of a plurality of the T-bars arranged in parallel in horizontallyspaced relationship;

(b) a pair of lamp support means oppositely disposed in horizontallyspaced relationship for receiving opposite ends of at least onefluorescent tube;

(c) means pivotally connecting each lamp support means to opposite endportions of the mounting means, with each pivotal axis extendingsubstantially perpendicular to the longitudinal axis of the mountingmeans and extending vertically when the mounting means rests transversethe T-bars;

(d) said pivotal connecting means being adapted to position the lampsupport means below and adjacent the T-b-ars on which the opposite endportions of the mounting means rest transversely;

(e) said connecting means being further adapted to locate each lampsupport means in a position laterally oifset from the longitudinal axisof the mounting means so that when the lamp support means is fastened toa T-bar the center of the lamp support means will lie directly beneath arespective cross T-bar which extends parallel to the mounting means;

(f) bar fastening means carried by each lamp support means for leasablyfastening the lamp support means to a flange of a respective T-bar;

(g) said bar fastening means being positioned a predetermined distanceapart by said connecting means so that the pair of lamp support meansare adapted to be fastened to selected spaced apart T-bars; and

(h) means slidable on each end portion of the mounting means along itslongitudinal axis for engaging a side of a respective cross T-bar torestrain longitudinal movement of the lighting fixture.

2. A unitary lighting fixture adapted for rapid installation on asuspended ceiling having spaced apart elongated structural memberscomprising:

(a) an elongated mounting means adapted to rest transversely across thetops of the structural members;

(b) a pair of lamp support means for receiving at least one lightingelement;

(c) means connecting each lamp support means to the mounting means sothat the lamp support means are located below said suspended ceilingwhen the mounting means rests on the ceiling structural members;

(d) at least one of said connecting means being a pivotal connectionWith the pivotal axis thereof extending substantially perpendicular tothe longitudinal axis of the mounting means and extending verticallywhen the mounting means rests on the ceiling structural members; and

(e) means carried by the elongated mounting means for fastening eachlamp support means to a respective ceiling structural member;

whereby the lighting fixture can be easily and quickly installed byfastening a pivoted lamp support means toa first ceiling structuralmember and then pivoting the other lamp support means about the pivotalconnection to fasten the other lamp support means to a second ceilingstructural member.

3. A unitary fluorescent lighting fixture adapted for rapid andsimplified installation on a suspended ceiling having a grid arrangementof inverted T-bars and cross T-bars comprising:

(a) an elongated mounting means adapted to rest transversely across thetops of a plurality of the T- bars arranged in parallel in horizontallyspaced relationship;

(b) a pair of lamp support means oppositely disposed in horizontallyspaced relationship for receiving opposite ends of at least onefluorescent tube;

(0) means connecting each lamp support means to the mounting means, saidconnecting means being adapted to position the lamp support means belowand adjacent to the T-bars on which the opposite end portions of themounting means rest transversely;

(d) the connecting means connecting at least one of said lamp supportmeans being a pivotal connection with the pivotal axis extendingsubstantially perpendicular to the longitudinal axis of the mountingmeans and extending vertically when the mounting means rests transversethe T-bars;

(e) bar fastening means carried by each lamp support means forreleasably fastening the lamp support means to a flange of a respectiveT-bar;

whereby the lighting fixture can -be easily and quickly installed byfastening the pivoted lamp support means to a first T-bar and thenpivoting the other lamp support means about the pivotal connection tofasten the other lamp support means to a second T-bar.

4. A lighting fixture as claimed in claim 3 wherein the mounting meansincludes an elongated hollow channel opening upwardly with upwardlyextending legs and an elongated top slidably engaging the tops of thechannel legs to open and close the channel.

5. A lighting fixture as claimed in claim 3 wherein the bar fasteningmeans includes clips slidably engaging the horizontal flange portion ofa respective T-bar.

6. A lighting fixture as claimed in claim 3 wherein the connecting meansare further adapted to locate each lamp support means in a positionlaterally offset from the longitudinal axis of the mounting means sothat when the lamp support means is fastened to a T-bar, the center ofthe lamp support means will lie directly beneath a respective crossT-bar which extends parallel to the mounting means.

7. A lighting fixture as claimed in claim 3 wherein the mounting barincludes restraining means to preclude twisting movement of the lightingfixture when installed on the ceiling.

8. A lighting fixture as claimed in claim 3 wherein weight means isreleasably mounted on top of the mounting means.

9. A lighting fixture as claimed in claim 4 wherein the pivotalconnecting means includes a cylinder rotatable within the hollow channeland lamp support means.

10. A lighting fixture as claimed in claim 4 wherein each lamp supportmeans includes a socket platform and at least one lamp socket.

11. A lighting fixture as claimed in claim 5 wherein the clips areformed from a surface of the lamp support means.

12. A lighting fixture as claimed in claim 7 wherein the restrainingmeans includes end plates on the mounting 7 means provided with lugs forengaging the vertical portions of adjacent T-bars.

ReferencesCited UNITED STATES PATENTS 2,291,489 '7/ 1942 Naysmith24051.1 1 2,440,603 3/ 1947 Guth 240-147 2,463,046 3/ 1949 Naysmith 24028 Schwartz 52-28 Pascucci 248-343 Kalbrunner 24078 Waller 2409 NQRTONANSHER, Primary Examiner.

W. M. FRYE, Assistant Examiner.

2. A UNITARY LIGHTING FIXTURE ADAPTED FOR RAPID INSTALLATION ON ASUSPENDED CEILING HAVING SPACED APART ELONGATED STRUCTURAL MEMBERSCOMPRISING: (A) AN ELONGATED MOUNTING MEANS ADAPTED TO REST TRANSVERSELYACROSS THE TOPS OF THE STRUCTURAL MEMBERS; (B) A PAIR OF LAMP SUPPORTMEANS FOR RECEIVING TO REST ONE LIGHTING ELEMENT; (C) MEANS CONNECTINGEACH LAMP SUPPORT MEANS TO THE MOUNTING MEANS SO THAT THE LAMP SUPPORTMEANS ARE LOCATED BELOW SAID SUSPENDED CEILING WHEN THE MOUNTING MEANSRESTS ON THE CEILING STRUCTURAL MEMBERS; (D) AT LEAST ONE OF SAIDCONNECTING MEANS BEING A PIVOTAL CONNECTION WITH THE PIVOTAL AXISTHEREOF EXTENDING SUBTANTIALLY PERPENDICULAR TO THE LONGITUDINAL AXIS OFTHE MOUNTING MEANS AND EXTENDING VERTICALLY WHEN THE MOUNTING MEANSRESTS ON THE CEILING STRUCTURAL MEMBERS; AND